Various approaches to automated or semi-automated three-dimensional object production or Rapid Prototyping & Manufacturing (RP&M) have become available in recent years, characterized in that each proceeds by building up three dimensional objects from three dimensional computer data descriptive of the objects in an additive manner from a plurality of formed and adhered laminae. These laminae are sometimes called object cross-sections, layers of structure, object layers, layers of the object, or simply layers (if the context makes it clear that solidified structure of appropriate shape is being referred to). Each lamina may represent a cross-section of a three-dimensional object, or may be a complete structure itself. Typically lamina are formed and adhered to a stack of previously formed and adhered laminae. In some RP&M technologies, techniques have been proposed which deviate from a strict layer-by-layer build up process wherein only a portion of an initial lamina is formed and prior to the formation of the remaining portion(s) of the initial lamina, at least one subsequent lamina is at least partially formed. Examples of such literature include U.S. Pat. No. 5,130,064 to Smalley and Hull issued Jul. 14, 1992; U.S. Pat. No. 5,855,836 to Leyden and Hull issued Jan. 5, 1999; U.S. Pat. No. 6,366,825 to Smalley et al. issued Apr. 2, 2002; U.S. Pat. No. 8,373,905 to Erol et al., issued Feb. 12, 2013; U.S. Pat. No. 8,226,395 to Smith et. al. issued Jul. 24, 2012 and U.S. Pat. No. 8,512,024 to Pax issued Aug. 20, 2013. Other literature include Berman, B., 2012. 3D Printing: The New Industrial Revolution. Business Horizons, 55(2), pp. 155-162; and Gibson, I., Rosen, D. W., Stucker, B., 2010. Additive Manufacturing: Rapid Prototyping to Direct Digital Manufacturing. London: Springer.
According to one approach, a three-dimensional object is built up by applying successive layers of unsolidified, flowable material to a working surface, and then selectively exposing the layers to synergistic stimulation in desired patterns, causing the layers to selectively harden into object laminae which adhere to previously-formed object laminae. In this approach, material is applied to the working surface both to areas which will not become part of an object lamina, and to areas which will become part of an object lamina. Typical of this approach is Stereolithography (SL), as described in U.S. Pat. No. 4,575,330, to Hull. According to one embodiment of Stereolithography, the synergistic stimulation is radiation from a UV laser, and the material is a photopolymer. Another example of this approach is Selective Laser Sintering (SLS), as described in U.S. Pat. No. 4,863,538, to Deckard, in which the synergistic stimulation is IR radiation from a CO2 laser and the material is a sinterable powder. This first approach may be termed photo-based stereolithography. A third example is Three-Dimensional Printing (3DP) and Direct Shell Production Casting (DSPC), as described in U.S. Pat. Nos. 5,340,656 and 5,204,055, to Sachs, et al., in which the synergistic stimulation is a chemical binder (e.g. an adhesive), and the material is a powder consisting of particles which bind together upon selective application of the chemical binder.
According to a second such approach, an object is formed by successively cutting object cross-sections having desired shapes and sizes out of sheets of material to form object lamina. Typically in practice, the sheets of paper are stacked and adhered to previously cut sheets prior to their being cut, but cutting prior to stacking and adhesion is possible. Typical of this approach is Laminated Object Manufacturing (LOM), as described in U.S. Pat. No. 4,752,352, to Feygin in which the material is paper, and the means for cutting the sheets into the desired shapes and sizes is a CO2 laser. U.S. Pat. No. 5,015,312 to Kinzie also addresses building object with LOM techniques.
According to a third such approach, object laminae are formed by selectively depositing an unsolidified, flowable material onto a working surface in desired patterns in areas which will become part of an object laminae. After or during selective deposition, the selectively deposited material is solidified to form a subsequent object lamina which is adhered to the previously-formed and stacked object laminae. These steps are then repeated to successively build up the object lamina-by-lamina. This object formation technique may be generically called Selective Deposition Modeling (SDM). The main difference between this approach and the first approach is that the material is deposited only in those areas which will become part of an object lamina. Typical of this approach is Fused Deposition Modeling (FDM), as described in U.S. Pat. Nos. 5,121,329 and 5,340,433, to Crump, in which the material is dispensed in a flowable state into an environment which is at a temperature below the flowable temperature of the material, and which then hardens after being allowed to cool. A second example is the technology described in U.S. Pat. No. 5,260,009, to Penn. A third example is Ballistic Particle Manufacturing (BPM), as described in U.S. Pat. Nos. 4,665,492; 5,134,569; and 5,216,616, to Masters, in which particles are directed to specific locations to form object cross-sections. A fourth example is Thermal Stereolithography (TSL) as described in U.S. Pat. No. 5,141,680, to Almquist et. al.
Three dimensional fabrication (herein referred to as 3D printing, without limitation) is essentially a method of building up a model by the deposition of multiple layers of material. The choice of input material used for producing any given model or part thereof thus governs many of the model's properties. Examples of such properties include but are not limited to those of mechanical, optical, thermal, conductive and chemical nature. Additionally, input materials suitable for 3D printing must meet specialized requirements to ensure facile processing. Product/model stability likewise is demanding. Restrictions on the suitability of materials adds to the complexity to identify improved input materials. Thus there is a great need to further improve properties of 3D printing inputs.